Many people set out feeders which contain seeds and other food items intended to attract various types of birds. However, a variety of other animals are often also attracted to such bird feeders, including rodents. Squirrels in particular can be surprisingly adept at accessing food contained in bird feeders, and are often able to circumvent measures taken in an attempt to protect feeders from intruders. Once a rodent has successfully obtained food from a feeder, the rodent is highly likely to return often in the search for more food. As a consequence, many residential complexes do not permit bird feeders on the premises since the attraction of rodents can create a nuisance for the residents.
There exist a variety of prior art solutions relating to preventing rodents or other invaders from accessing food in feeders. Examples include:    U.S. Pat. No. 7,798,099;    U.S. Pat. No. 6,986,322;    U.S. Pat. No. 6,543,384;    U.S. Pat. No. 6,253,706;    U.S. Pat. No. 5,361,723;    U.S. Pat. No. 5,323,735;    U.S. Pat. No. 5,291,855;    U.S. Pat. No. 4,389,975;    U.S. Pat. No. 3,090,354;    U.S. Pat. No. 3,086,499;    U.S. Pat. No. 3,051,126;    U.S. Pat. No. 2,931,336;    CA Patent No. 2349886;    CA Patent No. 2196225;    US Patent Application Publication No. 2007/0283894;    U.S. Pat. No. 6,539,892;    U.S. Pat. No. RE38182;    U.S. Pat. No. 2,891,508; and,    GB Patent No. 2367230.
The inventors have determined a need for improved apparatus and methods for protecting feeders from unwanted intruders.